Dipole IN a rain gutter..
Our vacation house has about 75 of plastic rain gutters on 3 sides of
the flat roof at about 20 feet up (2 story). I was thinking about laying a 40m dipole in there with no connection to anything on the house. The only question I have is, is that there is a 2" strip of metal flashing about 8 inches above the gutter, for the length of it. How bad do you think this would screw up a dipole that's essentially parallel to it? This station would be for emergency use primarily to talk with a station about 85 miles away with mountains in between so it doesn't need screaming dx performance... ground waves and cloud warming is all that's necessary... Joey |
Dipole IN a rain gutter..
Joey wrote:
Our vacation house has about 75 of plastic rain gutters on 3 sides of the flat roof at about 20 feet up (2 story). I was thinking about laying a 40m dipole in there with no connection to anything on the house. The only question I have is, is that there is a 2" strip of metal flashing about 8 inches above the gutter, for the length of it. How bad do you think this would screw up a dipole that's essentially parallel to it? It will act somewhat like guy wires which can cause distortion in the radiation pattern and losses. With any luck, it will have a high impedance and not have much effect. Try it and see what happens. Worst case, you may need to cut a slit every 1/4 WL to keep the currents low. -- 73, Cecil http://www.w5dxp.com |
Dipole IN a rain gutter..
On Sat, 08 Sep 2007 12:53:38 GMT, Cecil Moore
wrote: Joey wrote: Our vacation house has about 75 of plastic rain gutters on 3 sides of the flat roof at about 20 feet up (2 story). I was thinking about laying a 40m dipole in there with no connection to anything on the house. The only question I have is, is that there is a 2" strip of metal flashing about 8 inches above the gutter, for the length of it. How bad do you think this would screw up a dipole that's essentially parallel to it? It will act somewhat like guy wires which can cause distortion in the radiation pattern and losses. With any luck, it will have a high impedance and not have much effect. Try it and see what happens. Worst case, you may need to cut a slit every 1/4 WL to keep the currents low. Thanks, I may just whip up a dipole and do that! Was also looking at a RadioWavz Bazooka on 40m as well... dunno how that would compare since it radiates differently... only one way to find out! |
Dipole IN a rain gutter..
Joey joey29034atyawwhodotcom wrote in
: Thanks, I may just whip up a dipole and do that! Was also looking at a RadioWavz Bazooka on 40m as well... dunno how that would compare since it radiates differently... only one way to find out! Wow, a miracle antenna. Their claims include: Advantages: * Broad bandwidth * Almost unaffected by environment * Positive gain with reference to a common dipole operating under the same relative conditions up to 3.6 db * Greatly attenuates harmonics(almost eliminates interference!!! * Substantial decrease in static charge build-up * Non-directional. (as a inverted V) * Great for DX!!! Can you believe that? But wait, you wanted mo http://www.radiowavz.com/html/bazookas.htm . My study of a typical Double Bazooka antenna system at http://www.vk1od.net/DoubleBazooka/index.htm indicates that although it might have slightly greater VSWR bandwidth (FWIW), it has more loss than a conventional dipole. Though it is likely to be poorer, I doubt you would notice it... but why go to the trouble and expense for something that is likely to be poorer? Owen |
Dipole IN a rain gutter..
On Sep 8, 7:09 pm, Owen Duffy wrote:
My study of a typical Double Bazooka antenna system athttp://www.vk1od.net/DoubleBazooka/index.htmindicates that although it might have slightly greater VSWR bandwidth (FWIW), it has more loss than a conventional dipole. I believe Walter Maxwell also wrote an article about that a few years back. There is no free lunch with the double bazookas. I don't use them myself. Not so much because of the slight extra loss, more that coax weighs too much to use as antenna wire unless you have really strong supports. Regular wire is also a good bit cheaper. :/ MK |
Dipole IN a rain gutter..
On Sep 8, 7:09 pm, Owen Duffy wrote:
My study of a typical Double Bazooka antenna system athttp://www.vk1od.net/DoubleBazooka/index.htmindicates that although it might have slightly greater VSWR bandwidth (FWIW), it has more loss than a conventional dipole. I believe Walter Maxwell also wrote an article about that a few years back. There is no free lunch with the double bazookas. I don't use them myself. Not so much because of the slight extra loss, more that coax weighs too much to use as antenna wire unless you have really strong supports. Regular wire is also a good bit cheaper. :/ MK |
Dipole IN a rain gutter..
|
Dipole IN a rain gutter..
sounds like a regular dipole will do the same for less :) always interesting to see different designs and opinions tho!! On Sat, 08 Sep 2007 20:37:11 -0700, wrote: On Sep 8, 7:09 pm, Owen Duffy wrote: My study of a typical Double Bazooka antenna system athttp://www.vk1od.net/DoubleBazooka/index.htmindicates that although it might have slightly greater VSWR bandwidth (FWIW), it has more loss than a conventional dipole. I believe Walter Maxwell also wrote an article about that a few years back. There is no free lunch with the double bazookas. I don't use them myself. Not so much because of the slight extra loss, more that coax weighs too much to use as antenna wire unless you have really strong supports. Regular wire is also a good bit cheaper. :/ MK |
Dipole IN a rain gutter..
wrote:
I believe Walter Maxwell also wrote an article about that a few years back. http://www.w2du.com/r2ch18.pdf (Sec. 18.3 Resistive Losses) -- 73, Cecil http://www.w5dxp.com |
Dipole IN a rain gutter..
On Sat, 08 Sep 2007 20:31:05 -0700, wrote:
I believe Walter Maxwell also wrote an article about that a few years back. There is no free lunch with the double bazookas. I don't use them myself. Not so much because of the slight extra loss, more that coax weighs too much to use as antenna wire unless you have really strong supports. Regular wire is also a good bit cheaper. :/ MK Here's the article: http://www.w2du.com/r2ch18.pdf Danny, K6MHE |
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